[1]} study topic shifting for a target-guided conversation scenario where the system chats naturally with humans on open-domain topics and proactively guides the conversation to a designated target subject. As illustrated in Figure REF , given a target “e-books” and an arbitrary starting topic such as “tired”, the system drives the conversation following a topic path and effectively reaches the target in the end. Such a target-guided conversation setup is general-purpose and can entail a wide range of goal-directed dialog applications, including conversational exploratory search.
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